A radio access network (RAN) typically includes base transceiver stations (BTSs), each of which may include one or more antennas. In each coverage area, a BTS may receive a signal from each antenna. Additionally, the RAN may operate in a variety of multiple-antennas modes, such as a multiple-input and multiple-output (MIMO) mode, a multiple-input and single-output (MISO) mode, or a single-input and multiple-output (SIMO) mode. Further, the RAN may also use various modulation schemes. In one example, the RAN may use orthogonal frequency-division multiplexing (OFDM) to transmit on multiple subcarriers within a single radio channel. The OFDM modulation scheme is used in wireless communication systems such as IEEE 802.11 (WiFi) systems, IEEE 802.16 (WiMAX) systems, and systems that use the Long Term Evolution (LTE) specifications of the 3rd Generation Partnership Project (3GPP).
In the MIMO, MISO, and SIMO modes, at least one wireless link (sending and/or receiving) of the RAN involves multiple antennas of the BTS in communication with one wireless communication device (WCD). When operating the RAN in a MIMO mode, multiple antennas of a BTS may communicate with multiple antennas on a WCD. Each antenna at the BTS may have a corresponding antenna on the WCD. The antenna at the BTS and the corresponding antenna on the WCD may be known as an antenna pair. Thus, in a MIMO mode each antenna pair may be thought of as an individual spatial channel on which the BTS and the WCD may communicate. In MISO and SIMO modes, on the other hand, either the BTS or the WCD has multiple antennas and the corresponding device operates with only a single antenna. Thus, there may not be multiple spatial channels in a communication link between a WCD and a BTS when operating in either MISO or SIMO modes.
The foregoing background is illustrative only and is not intended to be in any way limiting. Nothing in the background section is intended as an admission of prior art.